Swaging machine

ABSTRACT

A swaging machine wherein the housing which accommodates radially movable dies is rotatable in a frame and wherein the holders for the dies receive motion from eccentric portions of shafts which are rotatable in the housing when the latter rotates in the frame. The shafts carry pinions meshing with a gear which is fixedly or rotatably mounted in the frame. The gear rotates the shafts and thereby reciprocates the dies in response to rotation of the housing in the frame.

United States Patent Brauer [451 Apr. 11, 1972 54] SWAGING MACHINE 2,562,643 7/1951 Saxer ..72/402 2 617 319 11/1952 Richards ..72/76 I t [72] Hans Bram" Lelchlmgen Germany 3,175,387 3/1965 Wichmann et a1 ..72/402 [73] Assignee: Th. Kieserling & Albrecht, Solingen, Gery Primary Examiner-Lowell A. Larson 22 Filed: Oct. 22 19 Attorney-Michael S. Striker [21] Appl. No.: 868,320 57 ABSTRACT A swaging machine wherein the housing which accommodates [30] Apphcmon Pnorlty Dam radially movable dies is rotatable in a frame and wherein the Oct. 24, 1968 Germany ..P 18 0 7 holders for the dies receive motion from eccentric portions of shafts which are rotatable in the housing when the latter 52] U.S. CL ..72/76, 72/402, 72/456 rotates in the frame- The Shafts Carry Piniohs meshing with a [51] I t, Cl, B21j 7/16, Bzlj 13/04 gear which is fixedly or rotatably mounted in the frame. The [58] Field of Search ..72/76, 402,408,456 gear rotates the shafts and thereby reciprocates the dies in response to rotation of the housing in the frame. 56 R f C'ted I l e 9 Claims, 3 Drawing Figures UNITED STATES PATENTS 771,921 10/1904 McGovern ..72/402 irate! 7 ma rm PATENTEDAPR 1 1 I972 SHEET 1 OF 3 INVENTOR. /A/ys B/muA-R PATENTEDAPR 1 1 I972 SHEET 2 UF 3 INVENTOR. Aw/ys 3/3405? SWAGING MACHINE BACKGROUND OF THE INVENTION The present invention relates to forging machines in general, and more particularly to improvements in swaging machines. Still more particularly, the invention relates to im provements in swaging machines of the type wherein the dies rotate about and move radially of the workpiece.

A drawback of many presently known swaging machines is that they produce considerable noise and/or that the wear on their pans is excessive. The trend in the design of machine tools is toward the production of machines whose operation is relatively quiet because a machine which produces excessive noise is likely to affect the concentration and health of the personnel. A presently known swaging machine whose operation is relatively quiet is disclosed in German DAS No. 1,199,589. This machine utilizes dies which need not orbit about the workpiece; however, the workpiece must be fed axially and must also rotate about its axis. The mechanism which controls and effects such composite movements of workpieces is rather complicated and contributes significantly to the initial and maintenance cost of the machine.

Axial feeding and continuous rotation of workpieces is also necessary in many conventional swaging machines of the type wherein the dies orbit about the workpiece. In the absence of any means for rotating the workpiece, the orbiting dies are likely to repeatedly strike against selected portions of the external surface of the workpiece so that the configuration and particularly the surface finish of the ultimate product is unsatisfactory. Moreover, all presently known swaging machines wherein the dies orbit about the workpiece produce considerable noise, not only during treatment of a workpiece but also during idling. Attempts to reduce such noise include the provision of springs which urge the dies radially and away from the workpiece and the provision of means for moving the dies radially inwardly against the opposition of such springs to thereby effect deforming engagement between the dies and the workpiece. In order to avoid rebounding of dies and the resulting generation of noise, such machines normally employ very strong helical springs. The outer sides of the dies are of sinusoidal outline and travel along several sets of rolls which cause the dies to move radially inwardly and to thereby stress the springs. Reference may be had to German Pat. No. 967,540. It was found that the wear on the parts of such machines is extremely high.

It is further known to mount the dies of a swaging machine in carriages which are movable radially and simultaneously orbit about the axis of the workpiece. In order to reduce noise, at least when the machine is idling, the carriages are coupled to fluid-operated pistons which urge them radially inwardly so that the carriages do not engage rollers which serve to move the carriages radially inwardly during treatment of a workpiece. This proposal has met with little success because the periods of idling are rather short, i.e., the intervals during which the noise level is bearable are short when compared with the overall length of the period during which the machine is in use. It was also found that the wear on carriages and on the parts which are in contact therewith is very high.

SUMMARY OF THE INVENTION An object of the invention is to produce a swaging machine which generates less noise than presently known machines, not only during treatment of workpieces but also during idling.

Another object of the invention is to provide a swaging machine wherein the wear on moving parts and on parts which contact such moving parts is considerably less than in presently known swaging machines.

A further object of the invention is to improve a swaging machine of the type wherein the workpiece need not rotate about its axis.

An additional object of the invention is to provide a swaging machine wherein the dies orbit about the axis of the workpiece and wherein such dies are capable of finishing the external surface of the workpiece with a high degree of precision despite the fact that the workpiece need not rotate about its own axis.

Still another object of the invention is to provide a swaging machine wherein the frequency at which the dies engage the workpiece can be varied in a novel and improved way.

The improved swaging machine comprises a frame, a housing which is rotatably mounted in the frame and can be driven by an electric motor or an analogous prime mover, preferably by way of a gear train, a plurality of shafts rotatably mounted in the housing and each having an eccentric portion, die holders each operatively connected with the eccentric portion of one of the shafts to perform radial movements with reference to the axis of the housing in response to rotation of the corresponding shafts about their respective axes, and novel means for rotating the shafts in the housing, including first gears each coaxially secured to one of the shafts, preferably externally of the housing, and a second gear fixedly or rotatably mounted in the frame and meshing with the first gears to effect rotation of the shafts about their own axes in response to rotation of the housing in the frame.

If the machine further includes a variable-speed drive for the second gear, the frequency of reciprocatory movement of the die holders in the housing can be varied without necessitating a change in rotational speed of the housing.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved swaging machine itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a longitudinal vertical sectional view of a swaging machine which embodies the invention, the section being taken in the direction of arrows as seen from the line A-B of FIG. 2;

FIG. 2 is a composite transverse vertical sectional view as seen in the direction of arrows from the line C-D (left-hand half) and from the line E-F (right-hand part) of FIG. 1; and

FIG. 3 is a horizontal sectional view as seen in the direction of arrows from the line G-H of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and 2, the improved swaging machine comprises a stationary frame or casing l which accommodates aligned antifriction bearings 2, 3 for a rotary housing 4. One axial end of the housing 4 is provided with a ring gear 5 which meshes with a pinion 6 mounted on a shaft 6a rotatably joumalled in the frame 1. The shaft 6a can receive torque from the output shaft 8a of an electric motor 8 through the intermediary of a clutch 7. The motor 8 is preferably of the variable-speed type.

The housing 4 accommodates two axially parallel shafts 9, 10 which are located diametrically opposite each other (see particularly FIG. 2) with reference to the axis of rotation of the housing and each of which includes an eccentric median portion 9e, 10e serving to effect radial reciprocatory movements of one of two tool holders or die holders 15, 16. The shafts 9, 10 respectively comprise coaxial trunnions 9a, 9b and 10a, 10b which are rotatable in roller bearings 11, 11a and 12, 12a provided therefor in the housing 4. The operative connections between the eccentric portions 92, l0e of the shafts 9, 10 and the holders 15, 16 respectively comprise roller bearings 13, 13a and 14, 14a, and the holders 15, 16 respectively support work-engaging dies including the dies l7, 18. Each of these dies is fixedly secured to the corresponding holder by means of four wedges or keys 20a, 20b, 20c, 20d. FIG. 3 shows the four keys 20a-20d for the die holder 16. These keys are movable lengthwise by means of feed screws including the screws 21, 21a, 21b shown in FIGS. 2 and 3. Each feed screw is provided with two sets of threads of opposite inclination and each such set of threads mates with complementary threads of one of the keys. Each of the holders 15, 16 can support several dies disposed end-to-end (see the dies 17, 17a and 18, 18a in FIG. 2).

The shafts 9, further comprise or are connected with end portions in the form of pins or stubs 90, 10c whose axes respectively coincide with the axes of the trunnions 9b, 10b and which are rigidly connected with pinions or gears 9d, 1011. These gears are outwardly adjacent to one end wall of the housing 4 and mesh with a further gear 22 which is shown as being fixedly mounted in the frame 1. When the motor 8 is started to rotate the housing 4, the shafts 9, 10 share such rotary movement of the housing and the gears 9d, 10d roll along the gear 22 to thereby cause rotation of the shafts 9, 10 about their own axes. Such movements of the shafts 9, 10 cause the holders l5, 16 to move their dies 17, 17a and 18, 18a radially inwardly and outwardly toward and away from engagement with a workpiece 23 which is fed axially in the passage of the housing 4 by a mechanism not shown in the drawing. The workpiece (e.g., a tube or pipe) need not be rotated about its own axis.

It is clear that the improved swaging machine can be used for calibrating tubes or like workpieces not only from without but also from within. The machine then employs a mandrel which is rotatably secured to an abutment or stop 24 best shown in FIG. 3. This stop serves to determine the extent to which the workpiece 23 can penetrate into the axial passage of the housing 4 and is adjustable axially by a sleeve 25 having external threads 25a which mesh with internal threads provided in a cover 26 of the frame 1. A lock nut 27 is employed to prevent uncontrolled axial displacements of the stop 24. Once the nut 27 is loosened, the operator can rotate the sleeve 25 to move the stop 24 and to thus determine in advance the extent to which the workpiece 23 can penetrate into the passage of housing 4. The sleeve 25 can move the stop 24 toward or away from the bearing 2.

In accordance with another feature of the invention, the frequency at which the dies 17, 17a and 18, 18a engage the workpiece during a given unit of time can be varied in a simple and time-saving manner by replacing the gear 22 with a gear which is rotatably mounted in the frame 1 and by providing an auxiliary drive which can rotate such gear at several speeds. The auxiliary drive may include a variable-speed motor, a motor and a variable-speed transmission, or a variable-speed transmission receiving motion from the motor 8. The rotational speed of the shafts 9, 10 about their own axes is thereby adjustable independently of the speed at which the housing 4 rotates in the frame 1.

The swaging machine further comprises means for confining the die holders 15, 16 to radial movement with reference to the axis of the housing 4 during rotation of the housing and during the resulting rotation of shafts 9, 10 about their own axes. As shown in FIGS. 2 and 3, the holders 15, 16 are respectively formed with bores 28, 28a for guide pins 29, 29a. One end of each of these guide pins is fixedly received in one of the holders and its other end is reciprocable in the other holder. FIG. 2 shows the guide pin 29 whose upper end portion is guided in a sleeve 30 and whose lower end portion is fixedly secured to the die holder 16. The mounting of the other guide pin 29a is the opposite of that of the pin 29, i.e., the pin 29a is reciprocable in a sleeve (not shown) of the holder 16 and is fixed in the registering bore of the holder 15.

An important advantage of the improved swaging machine is that it produces less noise than heretofore known swaging machines, not only when the axial passage of the housing 4 receives a workpiece but also when the machine is idling, i.e., when the motor 8 rotates the housing 4 prior to start or upon completion of treatment of a workpiece. Such quiet operation of the machine is attributed to the fact that the shafts 9, 10 cannot perform uncontrolled rotary movements in the housing 4 because their gears 9d, 10d are in permanent mesh with the a workpiece because the shafts 9, 10 and the holders l5, 16

are controlled at all times, i.e., not only during movement of the dies toward the axis of the housing 4 but also while the dies move away from engagement with the workpiece. It was also found that the wear on the parts of my swaging machine is less than in heretofore known machines. This is also attributed to the fact that the dies, their holders and the shafts are positively controlled and restricted in their movements during each stage of rotation of the housing 4 and irrespective of whether the housing 4 rotates during treatment of workpieces or during idling.

The manufacturing cost of the improved machine is less than the cost of many presently known machines because a large number of parts, including the antifriction bearings for the housing 4, for the shafts 9, l0 and for the die holders l5, 16, can constitute commercially available products. In many conventional machines, the parts serving to effect reciprocatory movements of the die holders must be specially produced in small numbers; such parts normally include annuli of rollers which engage the die holders and cause their movements with reference to the workpiece. Since my machine employs a large number of friction reducing parts, its efiiciency is high and the wear is moderate. The machine can employ a relatively simple work feeding device because the workpieces need not rotate about their axes. The transmission ratio between the gear 22 and the gears 9d, 10d can be readily selected in such a way that the dies invariably engage different portions of the external surface of a workpiece when the housing 4 rotates in the frame 1.

It is further clear that the improved swaging machine is susceptible of many modifications without departing from the spirit of my invention. For example, though the drawing shows a machine which, for the sake of clarity, includes only two die holders, it is equally possible to increase the number of die holders and hence the number of shafts. If the machine employs four die holders, the four shafts are preferably equidistant from each other and each die holder is coupled to the die holder which is located diametrically opposite with reference to the axis of the housing by guide pins or analogous confining means.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic an specific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. In a swaging machine, a combination comprising a frame; a housing rotatably mounted in said frame; a plurality of shafts rotatably mounted in said housing, each of said shafts having an eccentric portion; first and second die holders provided with bores extending normal to the axes of said shafts and in parallelism with one another, said die holders each being operatively connected with one of said eccentric portions to perform radial movements with reference to the axis of said housing in response to rotation of said shafts about their respective-axes; guide means being received in said bores of said first and second die holders and confining the same to radial movements with reference to the axis of said housing; and means for rotating said shafts in said housing, including first gears each coaxially secured to one of said shafts and a second gear mounted in said frame and meshing with said first gears to effect rotation of said shafts in response to rotation of said housing in said frame.

2. A combination as defined in claim 1, wherein the operative connections between said eccentric portions and the respective die holders include antifriction bearings.

3. A combination as defined in claim 1, wherein each of said shafts comprises an axially extending end portion located without said housing and wherein said first gears are fixed to said end portions of the respective shafts.

4. A combination as defined in claim 1, wherein said first and second holders are located substantially diametrically opposite each other with reference to the axis of said housing, said bores being registering bores and said pins each being fixedly received in a bore of one of said first and second holders and reciprocably extending into the registering bore of the other holder.

5. A combination as defined in claim 1, wherein said second gear is rotatable with reference to said frame.

6. A combination as defined in claim 5, further comprising means for rotating said second gear at a plurality of speeds. 

1. In a swaging machine, a combination comprising a frame; a housing rotatably mounted in said frame; a plurality of shafts rotatably mounted in said housing, each of said shafts having an eccentric portion; first and second die holders provided with bores extending normal to the axes of said shafts and in parallelism with one another, said die holders each being operatively connected with one of said eccentric portions to perform radial movements with reference to the axis of said housing in response to rotation of said shafts about their respective axes; guide means being received in said bores of said first and second die holders and confining the same to radial movements with reference to the axis of said housing; and means for rotating said shafts in said housing, including first gears each coaxially secured to one of said shafts and a second gear mounted in said frame and meshing with said first gears to effect rotation of said shafts in response to rotation of said housing in said frame.
 2. A combination as defined in claim 1, wherein the operative connections between said eccentric portions and the respective die holders include antifriction bearings.
 3. A combination as defined in claim 1, wherein each of said shafts comprises an axially extending end portion located without said housing and wherein said first gears are fixed to said end portions of the respective shafts.
 4. A combination as defined in claim 1, wherein said first and second holders are located substantially diametrically opposite each other with reference to the axis of said housing, said bores being registering bores and said pins each being fixedly received in a bore of one of said first and second holders and reciprocably extending into the registering bore of the other holder.
 5. A combination as defined in claim 1, wherein said second gear is rotatable with reference to said frame.
 6. A combination as defined in claim 5, further comprising means for rotating said second gear at a plurality of speeds.
 7. A combination as defined in claim 1, further comprising a gear train for rotating said housing in said frame.
 8. A combination as defined in claim 1, wherein said housing defines an axially extending passage for introduction of workpieces into the range of dies provided on said holders.
 9. A combination as defined in claim 8, further comprising stop means mounted in said frame and movable axially of said housing to determine the extent of penetration of workpieces into said passage. 